Osmotic diuresis due to urea as the cause of hypernatraemia in critically ill patients

Background. Hypernatraemia is common in critically ill patients and has been shown to be an independent predictor of mortality. Osmotic urea diuresis can cause hypernatraemia due to significant water losses but is often not diagnosed. Free water clearance (FWC) and electrolyte free water clearance (EFWC) were proposed to quantify renal water handling. We aimed to (i) identify patients with hypernatraemia due to osmotic urea diuresis and (ii) investigate whether FWC and EFWC are helpful in identifying renal loss of free water. Methods. In this retrospective study, we screened a registry for patients, who experienced intensive care unit (ICU)-acquired hypernatraemia. Among them, patients with hypernatraemia due to osmotic urea diuresis were detected by a case-by-case review. Total fluid and electrolyte balances together with FWC and EFWC were calculated for days of rising serum sodium and stable serum sodium. Results. We identified seven patients (10% of patients with ICU-acquired hypernatraemia) with osmotic diuresis due to urea. All patients were intubated during development of hypernatraemia and received enteral nutrition. The median highest serum sodium level of 153 mmol (Q1: 151-Q3: 155 mmol/L) was reached after a 5-day period of rise in serum sodium. During this period, FWC was −904 mL/day (Q1: −1574-Q3: −572), indicating renal water retention, while EFWC was 1419 mL/day (Q1: 1052-Q3: 1923), showing renal water loss. While FWC did not differ between time of stable serum sodium and development of hypernatraemia, EFWC was significantly higher during rise in serum sodium. Conclusion. Osmotic urea diuresis is a common cause of hypernatraemia in the ICU. EFWC was useful in the differential diagnosis of polyuria during rising serum sodium levels, while FWC was misleadin

Real Effective Exchange Rate Misalignment in the Euro Area: A Counterfactual Analysis

Were real effective exchange rates (REER) of Euro area member countries drastically misaligned at the outbreak of the global financial crisis? The answer is difficult to determine because economic theory gives no simple guideline for determining the equilibrium values of real exchange rates, and the determinants of those values might have been distorted as well. To overcome these limitations, we use synthetic matching to construct a counterfactual economy for each member as a linear combination of a large set of non-Euro area countries. We find that Euro area crisis countries are best described by a mixture of advanced and emerging economies. Comparing the actual REER with those of the counterfactuals gives sensible estimates of the misalignments at the start of the crisis: All peripheral countries were strongly overvalued, while high undervaluation is only observed for Finland

Acute health problems in African refugees: Ten years' experience in a Swiss emergency department

Summary: Background: Over the last two decades, the total number of applications from Africans for asylum in the countries of the European Union has increased from 578,000 to more than 2.9 million. About 20% (7,196/36,100) of the asylum seekers in Switzerland originate from Africa. The disease profile of African asylum seekers is remarkably different from that of the native population in the country of application. We have therefore conducted an analysis of African asylum seekers presenting themselves to our emergency department. Methods: In a retrospective analysis, the central patient registry database was searched for patients originating from Africa admitted from 1 January 2000 to 30 November 2011 and labelled as "Asylbewerber” (asylum seeker) or "Flüchtling” (refugee). Results: Three thousand six hundred and seventy-five African asylum seekers were admitted to our emergency department between 2000 and 2010. Thirty-four percent (n = 1,247) were female and 66% (n = 2,426) male. Eighty percent (n = 1,940) of the men and 70% (n = 823) of the women were younger than 40 years. Most of our patients originated from Algeria (n = 612). Forty-five percent (n = 1,628) of all patients presented with internal medical problems, 40% (n = 1,487) with injuries. 3.5% (n = 130) of all patients presented with psychiatric problems. Admission for psychiatric problems increased steadily from 2% (n = 4) in 2001 to 10% (n = 35) in 2011. Conclusion: The causes of presentation are manifold, including internal medical problems and injuries. Admissions for psychiatric problems are increasing. Establishing simple screening scores for somatization should be a key priority in providing more focused treatment in emergency department

Dysnatraemias in the emergency room: Undetected, untreated, unknown?

Zusammenfassung: HINTERGRUND: Hypo- und Hypernatriämie sind die häufigsten Elektrolytstörungen im Krankenhaus und wurden mit erhöhter Mortalität assoziiert. Zur Zeit gibt es nur wenige Daten zur Prävalenz der Dysnatriämien an der Notfallaufnahme sowie zu den Charakteristika der Patienten mit Hypo- und Hypernatriämien. METHODIK: In diese retrospektive Studie wurden Patienten welche zwischen 01.09.2010 und 30.11.2010 an der Notfallaufnahme einer Universitätsklinik eine Bestimmung des Serum-Natriums erhielten eingeschlossen. RESULTATE: Insgesamt wurden während des Studienzeitraumes an 3.182 Patienten Bestimmungen des Serum-Natriums durchgeführt. 124 Patienten (4 %) wiesen bei Aufnahme in die Notfallaufnahme eine Hyponatriämie auf, während 400 Patienten (13 %) eine Hypernatriämie aufwiesen. Es zeigte sich kein Unterschied im Alter zwischen jenen Patienten welche eine Hypernatriämie aufwiesen und jenen welche normonaträm waren. Patienten mit Hyponatriämie waren hingegen signifikant älter. SCHLUSSFOLGERUNGEN: Beinahe 1 von 5 Patienten weist bei Aufnahme an der Notfallaufnahme eine Störung des Natriumhaushalts auf. Im Gegensatz zu hospitalisierten Patienten war an der Notfallaufnahme die Prävalenz der Hypernatriämie bedeutend grösser als jene der Hyponatriämie. Überraschenderweise waren Patienten mit Hyponatriämie signifikant älter als jene mit Hypernatriämie und jene mit normalen Serum-Natriumwerte

Rising serum sodium levels are associated with a concurrent development of metabolic alkalosis in critically ill patients

Purpose: Changes in electrolyte homeostasis are important causes of acid-base disorders. While the effects of chloride are well studied, only little is known of the potential contributions of sodium to metabolic acid-base state. Thus, we investigated the effects of intensive care unit (ICU)-acquired hypernatremia on acid-base state. Methods: We included critically ill patients who developed hypernatremia, defined as a serum sodium concentration exceeding 149mmol/L, after ICU admission in this retrospective study. Data on electrolyte and acid-base state in all included patients were gathered in order to analyze the effects of hypernatremia on metabolic acid-base state by use of the physical-chemical approach. Results: A total of 51 patients were included in the study. The time of rising serum sodium and hypernatremia was accompanied by metabolic alkalosis. A transient increase in total base excess (standard base excess from 0.1 to 5.5mmol/L) paralleled by a transient increase in the base excess due to sodium (base excess sodium from 0.7 to 4.1mmol/L) could be observed. The other determinants of metabolic acid-base state remained stable. The increase in base excess was accompanied by a slight increase in overall pH (from 7.392 to 7.429, standard base excess from 0.1 to 5.5mmol/L). Conclusions: Hypernatremia is accompanied by metabolic alkalosis and an increase in pH. Given the high prevalence of hypernatremia, especially in critically ill patients, hypernatremic alkalosis should be part of the differential diagnosis of metabolic acid-base disorder

Temporal factors in violence related injuries—An 11year trend analysis of violence-related injuries from a Swiss Emergency Department

Summary: Background: Injury from interpersonal violence is a major social and medical problem in the industrialized world. Little is known about the trends in prevalence and injury pattern or about the demographic characteristics of the patients involved. Methods: In this retrospective analysis, we screened the database of the Emergency Department of a large university hospital for all patients who were admitted for injuries due to interpersonal violence over an 11year period. For all patients identified, we gathered data on age, country of origin, quality of injury, and hospitalization or outpatient management. A trend analysis was performed using Kendall's tau-b correlation coefficients for regression analysis. Results: The overall number of patients admitted to our Emergency Department remained stable over the study period. Non-Swiss nationals were overrepresented in comparison to the demographics of the region where the study was conducted. There was a trend toward a more severe pattern of injury, such as an increase in the number of severe head injuries. Conclusions: Although the overall number of patients remained stable over the study period, there was an alarming trend toward a more severe pattern of injury, expressed by an increase in severe head trauma

I-BEAT: New ultrasonic method for single bunch measurement of ion energy distribution

The shape of a wave carries all information about the spatial and temporal structure of its source, given that the medium and its properties are known. Most modern imaging methods seek to utilize this nature of waves originating from Huygens' principle. We discuss the retrieval of the complete kinetic energy distribution from the acoustic trace that is recorded when a short ion bunch deposits its energy in water. This novel method, which we refer to as Ion-Bunch Energy Acoustic Tracing (I-BEAT), is a generalization of the ionoacoustic approach. Featuring compactness, simple operation, indestructibility and high dynamic ranges in energy and intensity, I-BEAT is a promising approach to meet the needs of petawatt-class laser-based ion accelerators. With its capability of completely monitoring a single, focused proton bunch with prompt readout it, is expected to have particular impact for experiments and applications using ultrashort ion bunches in high flux regimes. We demonstrate its functionality using it with two laser-driven ion sources for quantitative determination of the kinetic energy distribution of single, focused proton bunches.Comment: Paper: 17 Pages, 3 figures Supplementary Material 16 pages, 7 figure

Hyponatremia in the emergency department.

Hyponatremia, defined as a serum sodium <135 mmol/L, is frequently encountered in patients presenting to the emergency department. Symptoms are often unspecific and include a recent history of falls, weakness and vertigo. Common causes of hyponatremia include diuretics, heart failure as well as Syndrome of Inappropriate Antidiuresis (SIAD) and correct diagnosis can be challenging. Emergency treatment of hyponatremia should be guided by presence of symptoms and focus on distinguishing between acute and chronic hyponatremia